[postgis-users] point to multipoint

[Mehmet Sirin]

hi, is someone out there who can explain how to make several points to a
multipoint.. i tried st_union and st_collect but what comes out is a
multilinestring and geometrycollection(string(..)) respectively.

code with which the unwilling multilinestring happens:

select astext(st_union(c.geom_4326)) from (
    select * from (select * from(
        select *,buffer(geom_4326,0.01)as buff from gc_berechnet where
name='Neuer Graben' and
        gemeinde='Osnabrück')a)b, zip_coordinates zc
where contains(buff,zc.geom) )c


what i want to do:
1.buffering a pointt (A) with a radius of 1km
2.take a look which other points lie in this buffer polygon
3.find out which point inside the buffer is nearest to the first point (A) i
buffered.
important for 3. : when having a multipoint i can easily use st_distance to
determine the closest point to point (A)


you can tell me how to create multipoint ? then i love you^^



leaving you kind regards
mehmet sirin c.
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